#Researchers Enlarge Brain Samples Making Them Easier to Image New technique enables nanoscale-resolution microscopy of large biological specimens.
The latest generation of so-called uper-resolutionmicroscopes can see inside cells with resolution better than 250 nanometers.
the researchers say. nstead of acquiring a new microscope to take images with nanoscale resolution,
if you are using blue-green light with a wavelength of 500 nanometers, you can see anything smaller than 250 nanometers. nfortunately,
in biology that right where things get interesting, says Boyden, who is a member of MIT Media Lab and Mcgovern Institute for Brain Research.
and other cellular activities are organized all at the nanoscale. Scientists have come up with some eally clever tricksto overcome this limitation,
you have to look at a large piece of tissue with nanoscale precision, he says. To achieve this, the MIT team focused its attention on the sample rather than the microscope.
but usually limited to a resolution of hundreds of nanometers. With their enlarged samples, the researchers achieved resolution down to 70 nanometers. he expansion microscopy process should be compatible with many existing microscope designs and systems already in laboratories,
Chen adds. Large tissue samples Using this technique, the MIT team was able to image a section of brain tissue 500 by 200 by 100 microns with a standard confocal microscope.
MIT researchers led by Ed Boyden have invented a new way to visualize the nanoscale structure of the brain and other tissues.
but also to see where all the nanoscale components are. While Boyden team is focused on the brain,
chemistry professor at Harvard university and lead author on the new paper published in the journal Nature Nanotechnology. ou can promote a positive interaction
Bao via e-mail. am impressed that they were able to inject even the nanowire transistors with very high yield.""
#'Wi-fi'Nanoparticles Send Signals from the Brain The problem with talking to our own brains,
A medical research team at Florida International University in Miami injected 20 billion nanoparticles into the brains of mice
the electric field can directly couple to the electric circuitry of the neural network. he nanoparticles could be used to deliver drugs to specific parts of the brain.
the nanoparticles could generate measurable magnetic fields in response to the brain electrical fields. Toggle the system back
which was a scant 25 nanometers deep. The holes had different diameters ranging from 45 to 75 nanometers
and corresponded to the desired absorption of light at various wavelengths. When light was shined onto the structure
Within each of the tiny particles is an elaborate nanopore structure think of it as a series of microscopic holes within a thin membrane,
Manufacturing these structures is part of an elaborate process that involves breaking down the nanopore structures into niform-sized particlesthat are fabricated ompletely
Gold nanoparticles Could Detect Disease: Discovery Newsprevious studies have shown that diseases such as lung and esophageal cancer,
New research suggests that a certain type of artificial diamond can be used as a nanoscale temperature probe with unmatched precision over time
but Jaque suspects theyl be most useful for observing the nanoscopic world, in particular the minute temperature fluctuations in living cells.
#Interplanetary comms get easier with a nanotech boost E t. MANAGED to phone home. But what about our own future Mars colonies or space probes millions of kilometres away?
Now a nanoscale light detector could make such deep-space missives easier to read. So says Richard Mirin at the US National Institute of Standards
Mirin made a nanowire detector that operates at-270 C. This boosted the number of photons it received each second by two orders of magnitude compared with regular detectors.
it will probably be thanks to MIT spinout QD Vision, a pioneer of quantum dot television displays.
Quantum dots are light-emitting semiconductor nanocrystals that can be tuned by changing their size, nanometer by nanometer to emit all colors across the visible spectrum.
By tuning these dots to red and green, and using a blue backlight to energize them,
Last June, Sony used QD Vision product, called Color IQ, in millions of its Bravia riluminostelevisions, marking the first-ever commercial quantum dot display.
and others developed a pioneering technique for producing quantum dot LEDS (QLEDS). To do so, they sandwiched a layer of quantum dots, a few nanometers thick, between two organic thin films.
When electrically charged, the dots illuminated a light bulb 25 times more efficiently than traditional devices.
became a landmark in the quantum dot-devices field. oon venture capitalists were calling Vladimir, asking if we spin a company out,
quantum dot displays. aking a transition like that from lighting to displays tests the nerves of folks involved, from top to bottom,
and last year became the first to market with a quantum dot display. Today, QD Vision remains one of only two quantum dot display companies that have seen their products go to market.
Now, with a sharp rise in commercial use, quantum dot technologies are positioned to penetrate the display industry
Coe-Sullivan says. Along with Color IQ-powered LCD TVS, Amazon released a quantum dot Kindle last year,
and Asus has a quantum dot notebook. nd there nothing in between that quantum dots can address,
he says. In the future, Coe-Sullivan adds, QD Vision may even go back and tackle its first challenge:
and value proposition for quantum dot lighting. n
#Hewlett Foundation funds new MIT initiative on cybersecurity policy MIT has received $15 million in funding from the William
#Two sensors in one MIT chemists have developed new nanoparticles that can simultaneously perform magnetic resonance imaging (MRI) and fluorescent imaging in living animals.
The researchers found that their imaging particles accumulated in the liver as nanoparticles usually do.
They have created also nanoparticles carrying the fluorescent agent plus up to three different drugs. This allows them to track
whether the nanoparticles are delivered to their targeted locations. That s the advantage of our platform we can mix
Steven Bottle a professor of nanotechnology and molecular science at Queensland University of Technology says the most impressive element of the study is the combination of two powerful imaging techniques into one nanomaterial.
From walls to nanoscale chips This fall Spielberg jumped to the other end of the 3-D printing spectrum, moving from walls to nanoscale fluidic chips.
He is now working in the lab of A. John Hart, the Mitsui Career development Associate professor of Mechanical engineering,
Testing their new approach in mice the researchers found that the chemotherapy drug temozolomide (TMZ) was more effective
For the new brain study the researchers delivered chemotherapy drugs via implantable microcapsules made of a biocompatible material called liquid crystal polymer.
because it is so difficult to get chemotherapy drugs to cross the blood-brain barrier. This could potentially positively impact patients lives says Lim who was involved not in the study.
#Nanoparticles get a magnetic handle A long-sought goal of creating particles that can emit a colorful fluorescent glow in a biological environment
The new technology could make it possible to track the position of the nanoparticles as they move within the body or inside a cell.
At the same time the nanoparticles could be manipulated precisely by applying a magnetic field to pull them along. And finally the particles could have a coating of a bioreactive substance that could seek out
It s been a dream of mine for many years to have a nanomaterial that incorporates both fluorescence
All of these goals are achieved by the new nanoparticles which can be identified with great precision by the wavelength of their fluorescent emissions.
and postdoc Ou Chen the nanoparticles crystallize such that they self-assemble in exactly the way that leads to the most useful outcome:
That puts the fluorescent molecules in the most visible location for allowing the nanoparticles to be tracked optically through a microscope.
because the starting material fluorescent nanoparticles that Bawendi and his group have been perfecting for years are themselves perfectly uniform in size.
The next step for the team is to test the new nanoparticles in a variety of biological settings.
Christopher Murray a professor of chemistry and materials science and engineering at the University of Pennsylvania who was connected not with this research says This work exemplifies the power of using nanocrystals as building blocks for multiscale and multifunctional structures.
The work was supported by the National institutes of health the Army Research Office through MIT s Institute for Soldier Nanotechnologies and the Department of energy y
#Fast cheap nanomanufacturing Luis Fernando Velsquez-Garc a s group at MIT s Microsystems Technology Laboratories (MTL) develops dense arrays of microscopic cones that harness
depositing or etching features onto nanoscale mechanical devices; spinning out nanofibers for use in water filters body armor and smart textiles;
or propulsion systems for fist-sized nanosatellites. In the latest issue of the IEEE Journal of Microelectromechanical systems Velsquez-Garc a his graduate students Eric Heubel and Philip Ponce de Leon and Frances Hill a postdoc in his group describe a new prototype
array that generates 10 times the ion current per emitter that previous arrays did. Ion current is a measure of the charge carried by moving ions
and height of the nanotubes the researchers were able to achieve a fluid flow that enabled an operating ion current at very near the theoretical limit.
That s crucial for nanofabrication applications in which the depth of an etch or the height of deposits must be consistent across an entire chip.
To control the nanotubes growth the researchers first cover the emitter array with an ultrathin catalyst film
The nanotubes grow up under the catalyst particles which sit atop them until the catalyst degrades.
The emitters like most nanoscale silicon devices were produced through photolithography a process in which patterns are transferred optically to layers of materials deposited on silicon wafers;
Nanoprintingvelsquez-Garca believes that using arrays of emitters to produce nanodevices could have several advantages over photolithography the technique that produces the arrays themselves.
and don t require a vacuum chamber the arrays could deposit materials that can t withstand the extreme conditions of many micro-and nanomanufacturing processes.
In my opinion the best nanosystems are going to be done by 3-D printing because it would bypass the problems of standard microfabrication Velsquez-Garca says.
Using their nanotube forest they re able to get the devices to operate in pure ion mode
For this study Yanik s team developed a new technology to inject RNA carried by nanoparticles called lipidoids previously designed by Daniel Anderson an associate professor of chemical engineering member of the Koch Institute for Integrative Cancer Research and Institute
#The ability to identify useful drug delivery nanoparticles using this miniaturized system holds great potential for accelerating our discovery process Anderson says.
and tumor-suppressor gene p53 is deleted researchers injected mice with RNA-carrying nanoparticles. This mouse model reflects many of the hallmarks of human lung cancer
The nanoparticles are made of a small polymer lipid conjugate; unlike liver-targeting nanoparticles these preferentially target the lung
and are tolerated well in the body. They were developed in the laboratories of co-senior author Daniel G. Anderson the Samuel A. Goldblith Associate professor of Chemical engineering an affiliate of MIT's Institute of Medical Engineering and Science;
In this study researchers tested the nanoparticle-delivery system with different payloads of therapeutic RNA. They found that delivery of mir-34a a p53-regulated mirna slowed tumor growth as did delivery of sikras a KRAS-targeting sirna.
Next researchers treated mice with both mir-34a and sikras in the same nanoparticle. Instead of just slowing tumor growth this combination therapy caused tumors to regress
treatment with cisplatin a small-molecule standard-care chemotherapy drug; treatment#with nanoparticles carrying both mir-34a and sikras;
and treatment#with both cisplatin and the nanoparticles. They found that the nanoparticle treatment extended life just as well as the cisplatin treatment and furthermore that the combination therapy of the nanoparticles and cisplatin together extended life by about an additional 25 percent.
Potential for personalized cancer treatmentsthis early example of RNA combination therapy demonstrates the potential of developing personalized cancer treatments.
With efficient delivery of therapeutic RNA any individual small RNA or combination of RNAS could be deployed to regulate the genetic mutations underlying a given patient s cancer.
We took the best mouse model for lung cancer we could find we found the best nanoparticle we could use
However nanoparticles and other delivery methods now being developed for DNA and RNA could prove more effective in targeting other organs Sharp says.
In the near term the material could also be embedded in lab-on-a-chip devices to magnetically direct the flow of cells and other biological material through a diagnostic chip s microchannels.
Tiny ferromagnetic particles approximately 10 nanometers in diameter in the ferrofluid could allow precision control
Recently, scientists have explored ways to improve the efficiency of solar-thermal harvesting by developing new solar receivers and by working with nanofluids.
The latter approach involves mixing water with nanoparticles that heat up quickly when exposed to sunlight, vaporizing the surrounding water molecules as steam.
The difficulty significantly increases for nanoemulsions where the drop sizes are below a micron. To break down those emulsions crews use de-emulsifiers
The membranes combine a very thin layer of nanopores with a thicker layer of micropores to limit the passage of unwanted material
in order to block them Varanasi says which in the case of nanoemulsions leads to very small pores
an ingenious process that makes large holes on one side that penetrate most of the way through the material providing little resistance to flow as well as nanoscale holes on the other surface in contact with the emulsion to be separated.
The thin layer with nanoscale pores allows for separation and the thick layer with large pores provides mechanical support.
Solomon performed experiments showing the effectiveness of the membranes in separating nanoemulsions while maintaining integrity at high pressure.
Anish Tuteja an assistant professor of materials science and engineering at the University of Michigan who was involved not in this research calls it a very interesting and innovative approach to fabricating membranes that can separate out nanoemulsions.
Oil-water nanoemulsions are ubiquitous in a number of industries and these membranes could enable rapid separation of those emulsions with high purity and efficiency.
That combination of order and disorder contributes to eumelanin broadband absorption, the team found. t a naturally existing nanocomposite,
hat has very critical macroscopic properties as a result of the nanostructure. While eumelanin molecules all share a basic chemistry,
in part because it is a natural destination for nanoparticles. But now, in a study appearing in the May 11 issue of Nature Nanotechnology,
an MIT-led team reports achieving the most potent RNAI gene silencing to date in nonliver tissues.
Using nanoparticles designed and screened for endothelial delivery of short strands of RNA called sirna,
Anderson and Langer have developed previously nanoparticles, now in clinical development, that can deliver sirna to liver cells called hepatocytes by coating the nucleic acids in fatty materials called lipidoids.
because they resemble the fatty droplets that circulate in the blood after a high-fat meal is consumed. he liver is a natural destination for nanoparticles,
if you inject nanoparticles into the blood, they are likely to end up there. Scientists have had some success delivering RNA to nonliver organs
they did not enter liver hepatocytes. hat interesting is that by changing the chemistry of the nanoparticle you can affect delivery to different parts of the body,
the researchers used the nanoparticles to block two genes that have been implicated in lung cancer VEGF receptor 1 and Dll4,
which relies on a nanoparticle that carries two drugs and releases them at different times,
and Paula Hammond, the David H. Koch Professor in Engineering, describe the findings in the May 8 online edition of Science Signaling. think it a harbinger of what nanomedicine can do for us in the future,
who is a member of MIT Koch Institute for Integrative Cancer Research. ee moving from the simplest model of the nanoparticle just getting the drug in there
and targeting it to having smart nanoparticles that deliver drug combinations in the way that you need to really attack the tumor.
or more different chemotherapy drugs in hopes that a multipronged attack will be more successful than a single drug.
a chemical engineer who has designed previously several types of nanoparticles that can carry two drugs at once.
Furthermore, packaging the two drugs in liposome nanoparticles made them much more effective than the traditional forms of the drugs,
At the same time, Hammond lab is working on more complex nanoparticles that would allow for more precise loading of the drugs
and fine-tuning of their staggered release. ith a nanoparticle delivery platform that allows us to control the relative rates of release and the relative amounts of loading,
The work was funded by the National institutes of health, the Center for Cancer Nanotechnology Excellence, the Koch Institute Frontier Research Program supported by the Kathy and Curt Marble Fund for Cancer Research,
and work at the Center for Functional Nanomaterials at Brookhaven National Laboratory was supported by the U s. Department of energy t
and help doctors predict how a given patient will respond to chemotherapy drugs. The new test, described in the Proceedings of the National Academy of Sciences the week of April 21, can analyze four types of DNA repair capacity simultaneously, in less than 24 hours.
Such a test could also be used to predict patientsresponse to chemotherapy drugs, which often work by damaging cancer cellsdna,
The research was funded by the National Cancer Institute Centers of Cancer Nanotechnology Excellence and the U s army Research Office e
The particles determine how energy moves at the nanoscale. The efficiency of devices such as photovoltaics and LEDS depends on how well excitons move within the material he adds.
This allows us to see new things Deotare says making it possible to demonstrate that the nanoscale structure of a material determines how quickly excitons get trapped as they move through it.
Grossman team tried attaching the molecules to carbon nanotubes (CNTS), but t incredibly hard to get these molecules packed onto a CNT in that kind of close packing,
Kucharski says. But then they found a big surprise: Even though the best they could achieve was a packing density less than half of
called azobenzene, protrude from the sides of the CNTS like the teeth of a comb.
they were interleaved with azobenzene molecules attached to adjacent CNTS. The net result: The molecules were actually much closer to each other than expected.
The interactions between azobenzene molecules on neighboring CNTS make the material work, Kucharski says. While previous modeling showed that the packing of azobenzenes on the same CNT would provide only a 30 percent increase in energy storage,
the experiments observed a 200 percent increase. New simulations confirmed that the effects of the packing between neighboring CNTS,
as opposed to on a single CNT, explain the significantly larger enhancements. This realization, Grossman says,
opens up a wide range of possible materials for optimizing heat storage. Instead of searching for specific photoswitching molecules
contain colored stripes of nanocrystals that glow brightly when lit up with near-infrared light. These particles can easily be manufactured
and include several stripes of different colored nanocrystals, known as are earth upconverting nanocrystals. These crystals are doped with elements such as ytterbium, gadolinium, erbium,
and thulium, which emit visible colors when exposed to near-infrared light. By altering the ratios of these elements,
In this case, each polymer stream contains nanocrystals that emit different colors, allowing the researchers to form striped particles.
So far, the researchers have created nanocrystals in nine different colors, but it should be possible to create many more,
and youl never get the same combination. he use of these upconverting nanocrystals is quite clever and highly enabling,
and more efficient including targeted nanoparticles. Wen Xue a senior postdoc at the Koch Institute is also a lead author of the paper.
The work was supported in part by the Army Research Office, through MIT Institute for Soldier Nanotechnologies,
and other substances including living cells MIT engineers have coaxed bacterial cells to produce biofilms that can incorporate nonliving materials such as gold nanoparticles and quantum dots.
These peptides can capture nonliving materials such as gold nanoparticles incorporating them into the biofilms. By programming cells to produce different types of curli fibers under certain conditions the researchers were able to control the biofilms properties
and create gold nanowires conducting biofilms and films studded with quantum dots or tiny crystals that exhibit quantum mechanical properties.
If gold nanoparticles are added to the environment the histidine tags will grab onto them creating rows of gold nanowires and a network that conducts electricity.
along with the bacteria that produce histidine-tagged fibers resulting in a material that contains both quantum dots and gold nanoparticles.
Now, a team of MIT researchers wants to make plants even more useful by augmenting them with nanomaterials that could enhance their energy production
Using another type of carbon nanotube, they also modified plants to detect the gas nitric oxide. Together
these represent the first steps in launching a scientific field the researchers have dubbed lant nanobionics. lants are very attractive as a technology platform,
Supercharged photosynthesis The idea for nanobionic plants grew out of a project in Strano lab to build self-repairing solar cells modeled on plant cells.
the researchers embedded them with cerium oxide nanoparticles, also known as nanoceria. These particles are very strong antioxidants that scavenge oxygen radicals
photosynthetic activity measured by the rate of electron flow through the thylakoid membranes was 49 percent greater than that in isolated chloroplasts without embedded nanotubes.
and used a technique called vascular infusion to deliver nanoparticles into Arabidopsis thaliana, a small flowering plant.
the researchers applied a solution of nanoparticles to the underside of the leaf, where it penetrated tiny pores known as stomata,
the nanotubes moved into the chloroplast and boosted photosynthetic electron flow by about 30 percent.
What is the impact of nanoparticles on the production of chemical fuels like glucose? Giraldo says.
Strano lab has developed previously carbon nanotube sensors for many different chemicals, including hydrogen peroxide, the explosive TNT, and the nerve gas sarin.
When the target molecule binds to a polymer wrapped around the nanotube, it alters the tube fluorescence. e could someday use these carbon nanotubes to make sensors that detect in real time, at the single-particle level,
Giraldo says. his is a marvelous demonstration of how nanotechnology can be coupled with synthetic biology to modify
a professor of biomedical engineering at Boston University who was involved not in the research. he authors nicely show that self-assembling nanoparticles can be used to enhance the photosynthetic capacity of plants,
They are also working on incorporating electronic nanomaterials, such as graphene, into plants. ight now, almost no one is working in this emerging field,
and the chemical engineering nanotechnology community to work together in an area that has a large potential.
and Howard hughes medical institute investigator Sangeeta Bhatia relies on nanoparticles that interact with tumor proteins called proteases each
The MIT nanoparticles are coated with peptides (short protein fragments) targeted by different MMPS. These particles congregate at tumor sites where MMPS cleave hundreds of peptides
With the current version of the technology patients would first receive an injection of the nanoparticles then urinate onto the paper test strip.
To make the process more convenient the researchers are now working on a nanoparticle formulation that could be implanted under the skin for longer-term monitoring.
scientists have tried targeting them to lymph nodes using nanoparticles to deliver them, or tagging them with antibodies specific to immune cells in the lymph nodes.
Additional help came from MIT Institute for Soldier Nanotechnologies. Ball specifically credits former technology transfer specialist Lisa Shaler-Clark as instrumental in taking the APA rom the lab bench to the field.
#Creating synthetic antibodies MIT chemical engineers have developed a novel way to generate nanoparticles that can recognize specific molecules, opening up a new approach to building durable sensors for many different compounds
nanometer-thick cylinders made of carbon that naturally fluoresce when exposed to laser light. In the past, researchers have exploited this phenomenon to create sensors by coating the nanotubes with molecules,
such as natural antibodies, that bind to a particular target. When the target is encountered, the carbon nanotube fluorescence brightens
or dims. The MIT team found that they could create novel sensors by coating the nanotubes with specifically designed amphiphilic polymers polymers that are drawn to both oil and water, like soap.
This approach offers a huge array of recognition sites specific to different targets, and could be used to create sensors to monitor diseases such as cancer, inflammation,
or diabetes in living systems. his new technique gives us an unprecedented ability to recognize any target molecule by screening nanotube-polymer complexes to create synthetic analogs to antibody function,
which appears in the Nov 24 online edition of Nature Nanotechnology. Lead authors of the paper are recent Phd recipient Jingqing Zhang
Their approach takes advantage of a phenomenon that occurs when certain types of polymers bind to a carbon nanotube.
These loops form a new layer surrounding the nanotube, known as a corona. The MIT researchers found that the loops within the corona are arranged very precisely along the tube,
and alter the carbon nanotube fluorescence. Molecular interactions What is unique about this approach, the researchers say,
and the polymer before it attaches to the nanotube. he idea is that a chemist could not look at the polymer
It has to adsorb onto the nanotube and then, by having certain sections of the polymer exposed,
The researchers used an automated, robot-assisted trial and error procedure to test about 30 polymer-coated nanotubes against three dozen possible targets, yielding three hits.
They are now working on a way to predict such polymer-nanotube interactions based on the structure of the corona layers,
using data generated from a new type of microscope that Landry built to image the interactions between the carbon nanotube coronas
The research was funded by the National Science Foundation and the Army Research Office through MIT Institute for Soldier Nanotechnologies t
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